| With the development of industrial robot technology,intelligent grinding technology has become the mainstream trend.These technologies have high freedom and flexibility and can be used to grind and polish complex surfaces,such as aircraft skins,vehicle parts surfaces,and high-power turbine gear blades.However,due to the high precision and grinding force required for these surfaces,conventional polishing equipment is unable to perform these processes.Currently,most technology solutions still rely on handheld grinding tools,which are inefficient and unable to ensure constant contact force during grinding,resulting in low part grinding accuracy.In addition,a large amount of particles are generated during the grinding process,which poses health hazards to the grinder.In order to meet the requirement of precise control of grinding force by robots,this paper designs a pneumatic constant-force grinding and polishing end effector,builds a complete mathematical model based on the system,and proposes an improved fuzzy PID control algorithm.The main work of the paper includes:Firstly,to achieve the goal of a flexible structure,constant contact force,and fast response of the grinding and polishing end effector,this paper uses the functional requirement-mechanical structure mapping method to analyze the mechanical structure,design a constant-force grinding and polishing end effector driven by a low-friction cylinder,and minimize weight as a constraint.Secondly,a complete dynamic analysis of the constant force grinding device end effector is carried out,and a mathematical model of the end effector is established.Based on this,gas flow equations,force balance equations,and gas mass flow continuity equations are established,and they are all interconnected.By substituting specific performance parameters into the formulas,the transfer function of the control system is calculated,and the simulation of the grinding and polishing end effector is performed using the transfer function,drawing the Bode plot and verifying the stability of the system.Thirdly,in order to improve the efficiency of PID control,this paper proposes an improved North Eagle-Fuzzy PID control algorithm.Through this improvement,a more effective fuzzy PID control technology is obtained.Through MATLAB simulation analysis,the improved NGO algorithm can significantly improve the response speed and stability of the fuzzy PID control system,thus greatly improving the response speed of the system and having better robustness.Fourthly,in order to complete the control system of the constant force grinding and polishing end effector,an embedded software system is designed to complete peripheral initialization,as well as related designs such as power,gravity sensor amplification circuit,RS485 interface module,pneumatic pressure sensor circuit,electric proportional reversing valve control circuit,auxiliary circuit,and PCB drawing,providing a solid hardware foundation for the implementation of the control system.At the same time,the embedded software control system of the STM32 microcontroller is developed to achieve the complete function of the system,improve the reliability and safety of the control system.Finally,a PC-based control software with excellent human-machine interaction performance is developed using Labview software. |
